import axios from 'axios'
import type { AxiosInstance, AxiosRequestConfig, AxiosResponse } from 'axios'

const DEAFULT_LOADING = true

class AppRequest {
  instance: AxiosInstance
  interceptors?: AppRequestInterceptors
  showLoading: boolean

  constructor(config: AppRequestConfig) {
    // 创建axios实例
    this.instance = axios.create(config)

    // 保存基本信息
    this.showLoading = config.showLoading ?? DEAFULT_LOADING
    this.interceptors = config.interceptors

    // 使用拦截器
    // 1.从config中取出的拦截器是对应实例的拦截器
    this.instance.interceptors.request.use(
     // this.interceptors?.requestInterceptor,
     this.interceptors?.requestInterceptorCatch 
    )

    this.instance.interceptors.response.use(
      this.interceptors?.responseInterceptor,
      this.interceptors?.responseInterceptorCatch
    )

    // 2. 添加所有的实力都有的拦截器
    this.instance.interceptors.request.use(
      config => {
        return config
      },
      err => {
        return err
      }
    )

    this.instance.interceptors.response.use(
      res => {
        console.log(res)
        return res
      },
      err => {
        return err
      }
    )
  }

  request<T = any>(config: AppRequestConfig<T>): Promise<T> {
    return new Promise((resolve, reject) => {
      // 1.单个请求对请求config的处理
      if (config.interceptors?.requestInterceptor) {
        config = config.interceptors.requestInterceptor(config)
      }

      // 2.判断是否需要显示loading
      if (config.showLoading === false) {
        this.showLoading = config.showLoading
      }

      this.instance
        .request<any, T>(config)
        .then((res) => {
          // 1.单个请求对数据的处理
          if (config.interceptors?.responseInterceptor) {
            res = config.interceptors.responseInterceptor(res)
          }
          // 2.将showLoading设置true, 这样不会影响下一个请求
          this.showLoading = DEAFULT_LOADING

          // 3.将结果resolve返回出去
          resolve(res)
        })
        .catch((err) => {
          // 将showLoading设置true, 这样不会影响下一个请求
          this.showLoading = DEAFULT_LOADING
          reject(err)
          return err
        })
    })
  }

  get<T = any>(config: AppRequestConfig<T>): Promise<T> {
    return this.request<T>({ ...config, method: 'GET' })
  }

  post<T = any>(config: AppRequestConfig<T>): Promise<T> {
    return this.request<T>({ ...config, method: 'POST' })
  }

  delete<T = any>(config: AppRequestConfig<T>): Promise<T> {
    return this.request<T>({ ...config, method: 'DELETE' })
  }

  patch<T = any>(config: AppRequestConfig<T>): Promise<T> {
    return this.request<T>({ ...config, method: 'PATCH' })
  }
}

interface AppRequestInterceptors<T = AxiosResponse> {
  requestInterceptor?: (config: AxiosRequestConfig) => AxiosRequestConfig
  requestInterceptorCatch?: (error: any) => any
  responseInterceptor?: (res: T) => any
  responseInterceptorCatch?: (error: any) => any
}

interface AppRequestConfig<T = AxiosResponse> extends AxiosRequestConfig {
  interceptors?: AppRequestInterceptors<T>
  showLoading?: boolean
}

export default AppRequest